/*

   Derby - Class org.apache.derby.iapi.db.ConnectionInfo

   Copyright 2000, 2004 The Apache Software Foundation or its licensors, as applicable.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

 */

package org.apache.derby.iapi.db;

import org.apache.derby.iapi.sql.conn.LanguageConnectionContext;
import org.apache.derby.iapi.sql.conn.ConnectionUtil;
import org.apache.derby.iapi.error.StandardException;
import org.apache.derby.iapi.error.PublicAPI;
import java.sql.SQLException;

/**
 *
 * ConnectionInfo class provides static methods for getting information 
 * related to a JDBC connection.
 * 
 * When called from within the query language,
 * each method returns information about the connection from which it was called.
 * <p>
 * Use the methods of this class only within an SQL-J statement; do not call 
 * them directly. 
 */
 
public abstract class ConnectionInfo
{

	/** no requirement for a constructor */
	private ConnectionInfo() {}

	/**
	 * Get the last autoincrement value inserted into the column by 
	 * a statement in this connection.

	 <BR><B> In JDBC 3.0 an application should use the standard methods provided by
	 JDBC 3.0 to obtain generated key values. See java.sql.Statement.getGeneratedKeys().</B>
	 * 
	 * @param 	schemaName		Name of the schema.
	 * @param	tableName		Name of the table.
	 * @param 	columnName		Name of the column.
	 * 
	 * @return  the last value to be inserted into the named autoincrement
	 * column by this connection. Returns null if this connection has never
	 * inserted into this column.
	 *
	 * @exception SQLException if the current connection could not be
	 * 			  established properly.
	 */
	public static Long lastAutoincrementValue(String schemaName, 
											  String tableName,
											  String columnName)
			throws SQLException								  
	{
		// a static method can manipulate lcc?
		LanguageConnectionContext lcc = ConnectionUtil.getCurrentLCC();
		return lcc.lastAutoincrementValue(schemaName, tableName, columnName);
	}	
	
	/**
	 * <B>INTERNAL USE ONLY</B>
	 * (<B>THIS METHOD MAY BE REMOVED IN A FUTURE RELEASE</B>.)
	 * @throws SQLException on error
	 **/
	public static long nextAutoincrementValue(String schemaName,
											  String tableName,
											  String columnName
											  )
	     throws SQLException
	{
		LanguageConnectionContext lcc = ConnectionUtil.getCurrentLCC();
		try
		{ 
			return 
				lcc.nextAutoincrementValue(schemaName, tableName, columnName);
		}
		catch (StandardException se)
		{ 
			throw PublicAPI.wrapStandardException(se);
		}
	}	
}

